1. Field of the Invention
The present invention broadly relates to the prevention and/or alleviation of decubitus ulcers (bed sores) in patients confined to beds for extended periods of time, and, more particularly, is concerned with an improved cushion for facilitating the same.
2. Description of the Prior Art
An ever-present concern in the care of long-term bedridden patients is the possible development of decubitus ulcers or bed sores. They result from the pressure exerted on the skin and subcutaneous tissues by the skeletal bony prominences and the object on which the patient rests, such as a mattress. This pressure produces tissue anoxia or ischemia. The cutaneous tissues are progressively broken down leading to destruction of underlying soft tissue. Once this ulcer forms it is quite painful and very slow to heal. Bacterial infection are difficult to avoid and frequently prolong the healing process.
Several items have been devised for the purpose of alleviating the pressure over the bony prominences. The most frequently used items may be categorized as pressure spreading cushions, such as sheepskins, soft foam rubber and gel filled pads. These cushion devices suffer from two defects.
First, except for the gel filled pads, they do not evenly distribute pressure by increasing the contact area. The ideal situation would be to suspend the patient in a fluid without contacting it. This is attempted with the gel filled pad, but containment of the fluid only aggravates the other defect.
Second, these devices limit air circulation to the skin in contact with the cushion. The sheepskin is compressed by the weight of the patient and the pads and foam rubber trap and hold perspiration next to the skin, thereby accelerating the skin breakdown.
The ideal cushion would, therefore, be one that supports the patient in the manner of a fluid, but also permits free air circulation to the skin in contact with the cushion. U.S. Pat. No. 3,757,366 to Sacher discloses a cushion in which means are provided to facilitate circulation of air to the areas of patient contact with the cushion. However, the Sacher cushion falls far short of providing means to support the patient in the manner of a fluid. U.S. Pat. No. 3,459,179 to Olesen discloses a pad filled with plastic beads that will adapt to the shape of the supported part of the patient's body, but no provision is made for circulating air to the contact area.
Therefore, a need exists for a cushion to support a bedridden patient which ideally would have the conforming properties of a fluid and the permeability to gas flow of ordinary cotton cloth.